1. Field of the Invention
The present invention relates to a cushion forming apparatus and method of use therefore.
2. Background of the Invention
Polyurethane foam and other resilient materials have been used for seat cushions for many years in the upholstered furniture industry. Foam blocks of various dimensions and densities are cut then covered with fabric to form seat cushions for sofas, chairs and other furniture. Additionally, chair and sofa frames are likewise often partially wrapped with resilient foam prior to covering with a selected fabric to achieve the desired contours and appearance. It is also know to preassemble foam covered components, also known as a sub-assembly, at various shops which are then finally assembled as a cushion at a central plant to expedite the manufacturing process. For example, upholstered chair manufacturers may contract through “outside” sources to purchase a partial chair seat sub-assembly consisting of a wooden base having at least one contoured foam block glued thereto. The furniture maker, after receiving this sub-assembly, will cover it with a fabric and subsequently attaches it to a finished chair frame. A large number of such partial seat assemblies may be kept on hand by the furniture manufacturer so changes to the fabric type or style can be quickly made depending on the customer's needs.
Cushion sub-assemblies and finished cushion assemblies are considered cushions within the meaning of this application. In general a cushion sub-assembly will have an outer foam layer (e.g. a thin foam cover) whereas a finished cushion assembly will have an outer fabric layer (e.g. leather, fabric, etc.). Of course, a cushion sub-assembly will be made into a cushion assembly by adding a desired outer fabric layer over the outer foam layer. There are some finished cushions that are not formed over a cushion sub-assembly (i.e. they do not have a foam cover).
Examples of cushion forming apparatus are found in U.S. Pat. Nos. 6,365,087, 6,068,808, 5,562,873, 5,238,514, 3,325,329, 3,283,346 and 3,146,143. Several of these patents utilize a vacuum seal with a flexible membrane that is pulled around the cushion. It is difficult to maintain an appropriate seal and to draw enough of a vacuum. In addressing these problems, other of these patents utilize a ram pressing the components of a cushion into a membrane from behind. With a pressing into the membrane the forces or tension is along the deflected membrane such that the forces forming the cushion are a component of the tension in the membrane. Further the membrane on a rigid frame cannot be used to wrap around a cushion structure (i.e. beyond a vertical position).
There remains a need in the art to provide a simple, universal cushion forming apparatus and method. It is the object of the present invention to improve upon the prior art. With the known disadvantages and problems associated with the prior art seat cushion assemblies, the present invention was conceived and one of its objectives is to provide a distortable seat cushion mold that will allow a manufacturer to produce an attractive, uniform and consistent seat on each chair manufactured.
It is another objective of the present invention to provide a seat cushion that will allow the upholsterer ease and convenience in covering the cushion. It is still another objective of the present invention to provide a seat cushion that has no unsightly underlines and one that is contoured evenly throughout. It is yet another objective of the present invention to provide a method for forming a seat cushion in which a plurality of synthetic foam components are attached to a rigid base to form a smooth, even crown. It is still another objective of the present invention to provide a method for forming a seat cushion whereby a distortable seat cushion mold is used to insure uniformity in the crown.
Various other objectives and advantages of the present invention become apparent to those skilled in the art as a more detailed presentation of the invention is set forth below.